How to convert NSDate to integer to pass PHP date() as unix timestamp?

Question

I'm an objective-c beginner and I was assigned to create an iPhone app for our client. I have some background with Java but almost no experience in this objective-c and this is my first time to developping a complete application... Anyway, I'm currently stack at several problems. One of those problem is that I need to send an integer value for PHP's `date` function from my iOS app. I've been searching around for the solution, but all of them are dealing with opposite ways (int to `NSDate`), not `NSDate` to integer value. I tried solutions like answered here but it's obvious it returns double, not an integer... Or this but this couldn't get the `System time`. I know I could get current system's NSDate with: ``` NSDate *theDay = [NSDate dateWithTimeIntervalSinceNow:[[NSTimeZone systemTimeZone] secondsFromGMT]]; ``` But I could not figure out how to convert this to an integer (or long) value. I just need to get the same value as we can get in `Java` with `System.currentTimeMillis()`. Als…

Accepted Answer

To get the current date, you should use this:

```
NSDate *theDate = [NSDate date];
```

To get it in seconds since January 1st, 1970, as a double, you would use:

```
NSTimeInterval seconds = [[NSDate date] timeIntervalSince1970];
```

To get it in ms, simply multiply the previous value by 1000 and let the compiler cast it into an integer without needing any additional code:

```
long long milliseconds = [[NSDate date] timeIntervalSince1970] * 1000;
```

And as @HotLicks points out, while `System.currentTimeMillis()` is in GMT, if you need the local time, you could use:

```
long long milliseconds = ([[NSDate date] timeIntervalSince1970] 
                        + [[NSTimeZone defaultTimeZone] secondsFromGMT]) * 1000; 
```

(I think that most web services will want GMT though.)

How to convert NSDate to integer to pass PHP date() as unix timestamp?

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